Autistic spectrum disorder is said to be one of neurodevelopmental disorders characterized by the symptoms of social disorder (e.g., social communication disturbance, interpersonal mutual reaction disorder and the like), restricted repetitive modalities (e.g., behavior, interests, activities and the like) and the like (non-patent document 1). At present, a treatment method has not been established yet, and improvement of life has been attempted by prescribing drugs. For example, antipsychotic drugs are used for preventing aggressive behaviors and self-injurious behaviors, which are behavioral disorders associated with autism spectrum disorder. However, it is a symptomatic treatment and does not aim at permanent cure.
Therefore, a therapeutic drug effective for an autism spectrum disorder (particularly, medicament effective for social disorder) has been awaited at the medical site.
Non-patent document 2 discloses that ramelteon was administered to two patients with insomnia accompanied by autism to confirm a therapeutic effect of ramelteon on sleep disorder, and evaluates items relating to sleep disorder.
Patent document 1 discloses a combined use of 5HTR agent and the like and ramelteon, and discloses autism as an application.
Patent document 2 discloses (S)—N-[2-(2-methyl-7,8-dihydro-6H-indeno[5,4-d][1,3]oxazol-8-yl)ethyl]acetamide.
Non-patent document 3 suggests that the amount of melatonin decreases in patients with an autistic spectrum disorder and that ASMT involved in melatonin synthesis in the body is involved.
Non-patent document 4 discloses the results that melatonin metabolite (6-SM) in the urine of autism patients decreases during daytime, in the night and throughout the day, the results that the amount of urinary 6-SM at night and the severity of autism such as language ability and the like show a negative correlation, and the results that the amount of urinary 6-SM during the day and the IQ score and the like show a positive correlation.
Non-patent document 5 suggests that melatonin has a therapeutic effect on sleep disorder in children with insomnia and sleep disorder accompanied by autism spectrum disorder and vulnerability X (Fragile X) syndrome.
Non-patent document 6 reports that there are six tests in the past in which improvement of day-to-day behavior by nocturnal administration of melatonin was reported in autistic spectrum disorder patients, and the like.